nothing i know of. just years of experience.
1)Because Panasonic is cheating HD resolution by using an anamorphic trick. It really is 960 pixels – you gotta strech it out to fit 1280.
2)98% of 24p media is actually 23.976 media, and 98% of workflows should conform to that. DF and NDF are simply counting methods. They don’t affect the amount of frames